Every major Romantic Period composer was influenced by Beethoven in some way, but selecting just a few of them reveals the variety of ways in which that influence was felt. Hector Berlioz, Johannes Brahms, and Richard Wagner were very different composers, but each drew something significant from Beethoven.
Berlioz greatly admired Beethoven’s Sixth Symphony for its connection of each movement to scenes from nature. In his Symphonie fantastique, he extends this idea by subordinating the entire form of the piece to the feverish narrative he has developed to accompany the symphony. In this and other works, he pushed both to expand the size of the orchestra and the types of effects it created through unusual combinations of musical elements.
Johannes Brahms was much more conservative than Berlioz, and was not interested in pushing music toward narrative. He was satisfied for music to be simply music, though he did place emphasis on music’s emotional resonance, as was typical for Romantics. His works are explicitly designed as further developments of the old forms, as were many of Beethoven’s, rather than the more typical Romantic tendency to leave behind the old forms Beethoven had kept to.
Richard Wagner believed music ought to be combined with other arts to produce the most powerful effects, arguing that Beethoven’s inclusion of a chorus in the fourth movement of his Ninth Symphony had been a silent acknowledgment of this. He also believed strongly in the power of the artist as an individual genius, which Beethoven had certainly seemed, and worked to make himself just such a world-changing figure.
In addition, he goes beyond the large scale of Beethoven, and the even larger attempts of Berlioz to produce operatic works that break down traditional structures and sometimes seem to lack boundaries. In a sense, rather than imitating what Beethoven had done musically, he worked to be the kind of revolutionary figure Beethoven had been.
To sum up, though Beethoven was admired by all three (as well as many others), they drew very different conclusions from him. These widely different conclusions demonstrate the breadth of Beethoven’s ability, innovation, and influence. It would be too much to say that Beethoven single-handedly began the Romantic Period in music, as many others contributed to the cultural change that produced it. But his work greatly influenced the particular shape it took.